Apparatus and method for resectioning gastro-esophageal tissue

ABSTRACT

A system for stapling tissue comprises a flexible endoscope and an operative head including a pair of opposed, curved tissue clamping jaws sized to pass through an esophagus, the jaws being moveable with respect to one another between an open tissue receiving configuration and a closed tissue clamping configuration, a first one of the curved jaws including a stapling mechanism and a second one of the jaws including a staple forming anvil surface, the stapling mechanism including staple slots through which staples are fired arranged in a row extending from a proximal end of the first jaw to a distal end thereof in combination with a control handle which, when the operative head is in an operative position within one of a patient&#39;s stomach and esophagus, remains outside the patient, the control handle including a first actuator for moving the jaws relative to one another and a second actuator for operating the stapling mechanism.

FIELD OF THE INVENTION

The present invention relates to endoscopic devices for performinglocalized resections of gastro-esophageal lesions.

BACKGROUND OF THE INVENTION

Endoscopic surgical stapling apparatus are known in the art and areutilized to provide a variety of surgical procedures. For example, U.S.Pat. No. 5,040,715 to Green, et al. discloses an endoscopic staplingdevice configured to be inserted through a small entrance wound in theabdominal cavity to place rows of staples in body tissue. This devicehas a limited range of motion in that the stapling assembly at thedistal end of the instrument can only be rotated about the central axisof the instrument.

An endoscopic stapling apparatus purporting to have a greater range ofmotion is disclosed in U.S. Pat. No. 5,326,013 to Green et al. Thisdevice has an articulating stapling assembly mounted for pivotalmovement about an axis extending transverse to the central axis of theinstrument. An endoscopic stapling device designed to be insertedthrough a small incision in a body wall and purporting to have anincreased range of motion is described in U.S. Pat. No. 5,389,098 toTsuruta et al. A stapling assembly of this device curves away from acentral axis of the instrument to a 90.degree. angle so that it can moreeasily reach tissue spaced from the central axis. This device incisestissue clamped within the stapling assembly and places staggered linesof staples on both sides of the incision.

SUMMARY OF THE INVENTION

The present invention is directed to a system for stapling tissuecomprising a flexible endoscope and an operative head including a pairof opposed, curved tissue clamping jaws sized to pass through anesophagus, the jaws being moveable with respect to one another betweenan open tissue receiving configuration and a closed tissue clampingconfiguration, a first one of the curved jaws including a staplingmechanism and a second one of the jaws including a staple forming anvilsurface, the stapling mechanism including staple slots through whichstaples are fired arranged in a row extending from a proximal end of thefirst jaw to a distal end thereof in combination with a control handlewhich, when the operative head is in an operative position within one ofa patient's stomach and esophagus, remains outside the patient, thecontrol handle including a first actuator for moving the jaws relativeto one another and a second actuator for operating the staplingmechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a system according to an illustrativeembodiment of the present invention along with a partiallycross-sectional view of a patient showing a target portion of tissue tobe resected;

FIG. 2a shows the system of FIG. 1 inserted into the patient's body viathe mouth;

FIG. 2b shows a display of the image of a stapling apparatus of thesystem of FIG. 1 provided to a user;

FIG. 2c shows a cross-sectional view of the patient's esophagus with thestapling apparatus of FIG. 3 in position adjacent to the target portionof tissue;

FIG. 3 shows a perspective view of the system of FIG. 1 with jaws of thestapling apparatus open;

FIG. 4 shows a partially cross-sectional view of a proximal end of thestapling apparatus of FIG. 3 showing control cables for operating thejaws configured as when the jaws are open;

FIG. 5 shows a perspective view of the system of FIG. 1 with jaws of thestapling apparatus closed with a lower actuator lever on a controlhandle being actuated;

FIG. 6 shows a partially cross-sectional view of the control handle ofthe system of FIG. 5 showing a coupling between control cables foroperating the jaws and the lower actuator lever on the control handle;

FIG. 7 shows a partially cross-sectional view of a proximal end of thestapling apparatus of FIG. 5 showing control cables for operating astapling pusher of the stapling apparatus configured as when the loweractuator lever is actuated;

FIG. 8 shows a perspective view of the system of FIG. 1 with jaws of thestapling apparatus closed with an upper actuator lever on the controlhandle being actuated;

FIG. 9 shows a partially cross-sectional view of a portion of thecontrol handle of the system of FIG. 8 showing a coupling betweencontrol cables for operating the jaws and the upper actuator lever onthe control handle;

FIG. 10 shows a partially cross-sectional view of a proximal end of thestapling apparatus of FIG. 5 showing control cables for operating astapling pusher of the stapling apparatus configured as when the upperactuator lever is actuated;

FIG. 11 shows a partially cross-sectional view of a stapling assembly ofthe system of FIG. 1 grasping esophageal tissue;

FIG. 12 shows a partially cross-sectional view of the stapling assemblyof the system of FIG. 1 illustrating a mechanism for grosslyapproximating the jaws of the stapling assembly;

FIG. 13 shows a partially cross-sectional view of the stapling assemblyillustrating a mechanism for finely approximating the jaws in an initialposition;

FIG. 14 shows a perspective view of an I-beam member of the fineapproximation mechanism of FIG. 13;

FIG. 15 shows a partially cross-sectional view of the stapling assemblywith the fine approximation mechanism in a partially advanced position;

FIG. 16 shows a perspective view of the stapling assembly with aC-shaped clamp member thereof in an initial position;

FIG. 17 shows a perspective view of the C-shaped clamp member of FIG. 16rotated 180.degree. removed from the jaws;

FIG. 18 shows a cross-sectional view of the stapling assembly with theC-shaped clamp member in a partially advanced position;

FIG. 19 shows an alternate embodiment of the system according to thepresent invention with a lateral endoscope receiving lumen;

FIG. 20 shows the system of FIG. 19 with an endoscope received therein;

FIG. 21 shows a system in accord with the present invention positionedwithin the stomach to perform a procedure for the treatment of reflux;and

FIG. 22 shows a system in accord with the present invention positionedwithin the stomach to perform a stomach reduction procedure.

DETAILED DESCRIPTION

A detailed description of illustrative embodiments of the presentinvention is provided in conjunction with the attached drawings. In thedescriptions of the various embodiments and the corresponding drawings,like reference numerals refer to like elements.

A method and apparatus for resectioning anastomized lumenal tissue isdisclosed in U.S. Pat. No. 5,868,760 to McGuckin et al., the disclosureof which is hereby incorporated by reference in its entirety. Thedisclosed apparatus includes a flexible tubular body and a distaloperating capsule that may be inserted through either a naturallyoccurring body orifice or a surgical incision and guided to an operativesite endoscopically or using radiologic imaging guidance. In use thetarget tissue is stapled, cut and captured within the operating capsulefor removal from the body. The healthy tissue is thereby anastomized bysurgical staples.

FIG. 1 shows a system for resecting esophageal tissue according to anillustrative embodiment of the present invention. A surgical staplingapparatus, designated generally by the reference numeral 10, is utilizedin conjunction with an endoscope 20 for providing remote vision of anoperative area and to assist in guiding the stapling apparatus 10 to theoperative area. An endoscopic grasping device 30 extends through a lumenin the endoscope 20 for use at the surgical site as would be understoodby those of skill in the art. Those skilled in the art will furtherunderstand that, while the illustrative embodiments are described inconjunction with visual observation of the operative site via theendoscope 20, these procedures may also be visualized through the use ofMagnetic Resonance Imaging (MRI). In this case, components of the systemand the instruments utilized therewith, such as the grasping device 30,would be constructed from non-ferrous material such as titanium, aswould be understood by those of skill in the art.

As shown in FIG. 1, the stapling apparatus 10 includes a proximal handleportion 12, an elongated flexible body portion 14 extending from thehandle portion 12 and a generally C-shaped stapling assembly 16operatively associated with a distal end of the flexible body portion14. The flexible body portion 14 and the stapling assembly 16 arepreferably dimensioned and configured to traverse the natural curvatureof the esophagus. As shown in FIGS. 2b and 2c and described in detailbelow, the stapling assembly 16 includes a pair of opposable jaws 17defined by a staple carrying portion 40 and a staple forming portion 50.Those skilled in the art will understand that, although the jaws 17 aredescribed herein as rotating relative to one another between the openand closed positions, that these jaws 17 may be coupled by a mechanismwhich allows them to move linearly with respect to one another or in anyother manner so long as they move between a first position in which thejaws 17 are separated from one another to receive tissue and a secondposition in which the jaws 17 are clamped together to hold tissuetightly therebetween for stapling.

Furthermore, those skilled in the art will understand that the systemmay operate with any of a variety of commercially available medicalendoscopes which may include, for example, a proximal handle portion 22,an elongated flexible body portion 24 through which one or more interiorlumena extend for accommodating, for example, a fiber optic bundle orother image transmission structure, a working channel for the graspingdevice 30, etc. Those skilled in the art will understand that the fiberoptic bundle (or other image transmitting structure) allows a user toremotely visually monitor a field of view at the distal end of theendoscope (e.g., an operative site S within the esophagus E). As wouldbe further understood by those of skill in the art, the tissue graspingdevice 30 may include a handle portion 32, an elongated flexible bodyportion 34 and a pair of opposable jaws 36 a and 36 b.

In use as shown in FIGS. 2a -2 c, the surgical stapling apparatus 10 andthe flexible endoscope 20 are introduced into a patient's mouth andadvanced into the esophagus to the operative site S under visualguidance from the endoscope 20. Once at the site S, the operatormaneuvers the stapling assembly 16 into a desired position relative tothe tissue to be resected. Those skilled in the art will understand thatthe stapling assembly 16 may be coupled to the handle portion 22 by acable steering system (not shown) substantially as included incommercially available endoscopes to allow the remote maneuvering andpositioning of the stapling assembly 16. The jaws 17 of the staplingassembly 16 are then opened to a tissue receiving position as shown inFIG. 3 and the grasping device 30 is advanced from the distal end of theendoscope 20. The jaws 36 a and 36 b are rotated away from one anotherby manipulation of the grasper handle portion 32 and the tissue T to beresected is grasped by closing the jaws 36 a, 36 b. The grasping device30 is then withdrawn into the working channel of the endoscope 20 topull the tissue T into position between the jaws 17 of the staplingassembly 16 and the jaws 17 are closed to clamp the tissue T in placebetween the staple carrying portion 40 and the staple forming portion50. Those skilled in the art will understand that the tissue T ispreferably drawn between the jaws 17 so that a margin of healthy tissueis positioned between the staple carrying portion 40 and the stapleforming portion 50 to ensure that all of the diseased or damaged tissueT is removed. Those skilled in the art will understand that this may bevisually confirmed through the use of the vision system of the endoscopeas shown in FIG. 2 b.

As shown in FIG. 2c , once the tissue T has been properly positionedbetween the jaws 17, the jaws 17 are grossly approximated and are thenfinely approximated using a translating clamping member 60, illustratedin detail in FIGS. 16-18. As shown in FIGS. 3, 4 and 12, an illustrativeembodiment of the system according to the present invention includes anactuation cable 44 to facilitate gross approximation of the jaws 17 viaactuation of an actuator knob 38. The actuation cable 44 may be securedto the one of the jaws 17 including, for example, the staple carryingportion 40 and is operatively coupled to the other jaw 17 including thestaple forming portion 50 by a member 85 which may, for example, be aspindle, capstan or other member around which the cable 44 passes tochange direction to generate the clamping force to draw the jaws 17together. Furthermore, an overhanging flange 98 at a proximal end of thestaple carrying portion 40 acts as a tissue shield preventing the targettissue T from entering into the joint between the jaws 17.

As shown in FIGS. 3-7, to actuate the clamping member 60 to finelyapproximate the jaws 17, the lower clamping handle 12 a is actuated inthe direction of the arrow in FIG. 5 to cause the integral gear rack 62a to turn pinion gear 62 b which rotates elongated drive cable 64. Asshown in FIG. 7, the drive cable 64 is coupled to a drive screw 63 sothat rotation of the drive cable 64 rotates the drive screw 63 movingthe clamping member 60 distally as shown in FIG. 18. This finelyapproximates the jaws 17 of the stapling assembly 16 whereby a tissuecontacting surface of the staple carrying portion 40 and a tissuecontacting surface of the staple forming portion 50 are brought intocooperative alignment, tightly clamping the tissue therebetween. Thoseskilled in the art will understand that alternative sources of power(e.g., electrical, hydraulic, pneumatic, etc.) may be applied to drivethe jaws 17 and to drive all other mechanisms of the stapling assembly16.

As shown in FIG. 8, once the jaws 17 have been brought into cooperativealignment with one another, the stapling assembly 16 may be actuated tofire staples through the, clamped tissue while simultaneously cuttingaway the tissue T from the stapled and anastomized tissue. The useractuates the stapling assembly 16 to drive staples through the margin ofhealthy tissue in one or more arcuate bands located radially outward ofa line of tissue cutting. Alternatively, those skilled in the art willunderstand that the stapling operation may be separated from the tissuecutting operation so that no tissue is cut until the entire staplingoperation has been successfully concluded.

Specifically, as shown in FIGS. 8-10, the operator drives an I-beammember 70 through the stapling assembly 16 by operating the clampinghandle 12 b in the direction of the arrow in FIG. 8, causing gear rack72 a to rotate pinion gear 72 b which rotates a staple driving drivecable 74 as shown in FIG. 9. The drive cable extends through theflexible body portion 14 to a linear drive screw 76 which drives aflexible pusher 80 coupled to the I-beam member 70 as shown in FIG. 10.

As shown in FIGS. 11, 13, 14 and 15, the I-beam member 70 includes upperand lower beam portions 82 a, 82 b, respectively, connected by a centralweb portion 84. A leading edge 84 a of the central web portion 84 maypreferably define a cutting blade for incising tissue as the I-beammember 70 is moved distally as described below. As shown in FIG. 11, anarcuate channel 90 within which the central web portion 84 travels, isdefined in the opposing jaws 17 radially inward of the arcuate lines ofstaple carrying slots (not shown). Those skilled in the art willunderstand that the staple slots may be arranged in any number of rows,for example, from one to five such rows may be included and the slots ofthese rows may be staggered so that to ensure that the opening createdby the resection is completely sealed.

As described above, actuation of the lower handle 12 a causes theC-shaped clamp member 60 to move along an arc the length of the curvedstapling assembly 16 to finely approximate the jaws 17 toward oneanother. As shown in FIGS. 13, 14 and 15, the clamp member 60 includes abody portion 112 from which depend upper and lower clamping beams 114 aand 114 b, respectively, for urging the jaws 17 toward one another.

In addition, as shown in FIGS. 16 and 17, in one embodiment of theinvention, the body 112 includes a radially depending driving stem 115having a sloped leading edge configured to extend through an arcuateslot 116 formed in the staple carrying portion 40 for sequentiallycontacting each of a plurality of staple pushers 118. The staple pushers118 are positioned so that, when contacted by the driving stem 115, eachstaple pusher 118 is driven through a corresponding one of the stapleslots to drive a staple housed therein from the slot out of the staplecarrying portion 40, through both thicknesses of the folded portion oftissue clamped between the jaws 17 and against the staple formingsurface 50 a of the staple forming portion 50 to couple the twothicknesses of tissue to one another. In this embodiment, the clampingmember 60 further includes an integral cutting blade 130 for forming anarcuate incision substantially concentric with and radially within aninner one of the arcs of staple slots. Furthermore, the cutting blade130 is preferably positioned so that it trails the leading edge 115 sothat tissue is stapled before it is cut.

As shown in FIG. 15, according to a further embodiment of the invention,actuation of the upper actuation handle 12 b causes the I-beam member 70to move through the stapling assembly 16 to sequentially fire arcuaterows of staples while simultaneously cutting tissue away from theesophagus radially within the rows of staples. When the I-beam member 70is driven by the pusher 80, the sloped leading edge of the upper beamportion 82 a contacts sequentially each of a plurality of staple pushers118 to drive them through their respective staple slots to drive thestaples housed therein from each slot out of the staple carrying portion40, through both thicknesses of the folded portion of tissue clampedbetween the jaws 17 and into the staple forming pockets 122 formed inthe staple forming surface 50 a of the staple forming portion 50 tocouple the two thicknesses of tissue to one another. As the leading edge84 a of the central web portion 84 is proximal to the sloped leadingedge, the incision trails the stapling action so that only tissue withinthe arc that has previously been stapled is severed.

As shown in FIGS. 19 and 20, according to a further embodiment of theinvention, a stapling assembly 16′ according to the present inventionmay include an endoscope receiving lumen 140 through which the endoscope20 may be slidably inserted. This allows an operator to use to steeringand vision capability of the endoscope 20 to locate the operative siteS. Once the distal end of the endoscope 20 is positioned adjacent to thesite S, the stapling assembly 16′ may be slid along the endoscope 20 tothe operative site S and the steering capability of the distal end ofthe endoscope 20 may be employed to achieve a desired position andorientation of the stapling assembly 16′ relative to the tissue T. Otherthan the endoscope receiving lumen 140, the construction of the rest ofthe system of FIGS. 19 and 20 may be substantially in accord with thatof any of the previously described embodiments.

Furthermore, as shown in FIGS. 21 and 22, the system according to thepresent invention may also be used to perform resections within thestomach. For example, the stapling apparatus 10 may be used to correctgastro-esophageal reflux (“GERD”) or to perform a stomach reductionprocedure. Specifically, as shown in FIG. 21, a system according to theinvention may be inserted through the esophagus into a patient's stomachand the operator may position the jaws 17 under visual control via theendoscope 20 adjacent to a junction between the esophagus and thestomach. The operator then uses the steering capability of the endoscope20, received within the endoscope lumen 140 to direct the jaws 17 towarda portion of stomach tissue to be fastened to the esophagus.Specifically, the operator grasps a portion of the stomach using thegrasping device 30 and urges the tissue T toward the esophagus to createa fold of tissue with an outside surface of the stomach tissue adjacentto or in contact with an outer surface of the esophagus. This fold isthen clamped by the jaws 17 and stapled together to reduce the diameterof the opening from the esophagus to the stomach. The tissue radiallywithin the stapled tissue is then resected.

Similarly as shown in FIG. 22, to perform a stomach reduction, anoperator inserts a system according to the present invention into thestomach via the esophagus as described above in regard to FIG. 21 andlocates a portion of tissue to be folded over on itself to reduce thesize of the stomach. This tissue T is grasped by the grasping device 30and drawn between the jaws 17 which clamp the tissue T together foldedonto itself and staples the fold together. Those skilled in the art willunderstand that, for a stomach reduction procedure, the folded tissueradially within the staples may, if desired, be left in place withoutresection so that the operation may be reversed at a later date. Thus,for such a stomach reduction procedure where the folded, stapled tissuewill be left in place within the stomach, the stapling apparatus 10 neednot include a tissue cutting mechanism. Rather, the stapling apparatus10 need only include structure for approximating the jaws 17 and fordriving staples through the gripped fold of tissue. In this case, theC-shaped clamp member 60 would be constructed without the cutting blade130.

The above described embodiments are for purposes of illustration onlyand the various modifications of these embodiments which will beapparent are considered to be within the scope of the teachings of thisinvention which is to be limited only by the claims appended hereto.

1-20. (canceled)
 21. An apparatus, comprising: a head having a first jawand a second jaw, at least one of the first jaw and the second jaw beingmovable with respect to the other of the first jaw and the second jawfrom a first configuration in which the first jaw and the second jaw arespaced apart at a first distance and a second configuration in which thefirst jaw and the second jaw are spaced apart at a second distance, astapling assembly of the first jaw having slots through which staplesare configured to be passed in one or more rows extending from aproximal end of the first jaw to a distal end of the first jaw, and ananvil surface of the second jaw being configured to form a staple; afirst adjustment assembly configured for gross movement of the first jawor the second jaw; a second adjustment assembly including a beamconfigured for fine adjustment of the first jaw and the second jaw,wherein the beam is coupled to a pushing bar and includes a central webportion connecting an upper beam portion and a lower beam portion, aleading edge of the central web portion mostly being more distal than atrailing edge of the upper beam portion and a trailing edge of the lowerbeam portion and including a cutting blade, and a portion of the beamcontained within the first jaw being configured to cause a staple pusherto move for firing a staple as the beam moves in a proximal to distaldirection; a handle having one or more actuators configured to move atleast one of the first jaw and the second jaw from the firstconfiguration to the second configuration, and to actuate the staplingassembly; and a shaft coupling the handle to the head.
 22. The apparatusof claim 21, wherein one of the first jaw and the second jaw includes anoverhanging flange at a proximal end that extends past a surface of theother of the first jaw and the second jaw when the first jaw and secondjaw are in the first configuration and the second configuration.
 23. Theapparatus of claim 21, wherein the pushing bar is substantially longerthan the beam when measured in a proximal to distal direction, and thecentral web portion has a width approximately in a range of 50% to 100%of the greater of the upper beam portion's width and the lower beamportion's width when measured in a proximal to distal direction.
 24. Theapparatus of claim 21, further comprising a gear or a cable forcontrolling the gross movement or the fine adjustment.
 25. An apparatusfor stapling tissue, comprising: a first jaw and a second jaw, at leastone of the first jaw and the second jaw being movable with respect tothe other of the first jaw and the second jaw from a first configurationin which the first jaw and the second jaw are separated from each otherat a first distance to receive tissue to a second configuration in whichthe first jaw and the second jaw are clamped together at a seconddistance to hold tissue therebetween for stapling, a staple carryingportion of the first jaw defining slots through which staples areconfigured to pass, and an anvil surface defined on the second jawopposing the first jaw; at least one of a gear and a cable operativelycoupled to at least one of the first jaw and the second jaw andconfigured to move at least one of the first jaw and the second jaw fromthe first configuration to the second configuration such that the firstjaw and the second jaw are in alignment; and a staple pusher configuredto cause a staple to move from a first position at least partiallywithin the staple carrying portion to a second position entirely outsidethe staple carrying portion; the second distance and the alignment beingmaintained by a beam configured to engage at least one of the first jawand the second jaw at least partially from therewithin and to cause thestaple pusher to move as the beam moves from a proximal location to adistal location, the beam being coupled to a pushing bar which issubstantially longer than the beam when measured in a proximal to distaldirection.
 26. The apparatus of claim 25, wherein at least a portion ofthe beam is configured to engage the first jaw or the second jawentirely from therewithin to maintain the second distance and thealignment.
 27. The apparatus of claim 25, wherein the beam includes anupper beam portion, a lower beam portion, and a central web portionconnecting the upper beam portion and the lower beam portion, and aleading edge of the central web portion includes a cutting blade and isgenerally more distal than a trailing edge of the upper beam portion anda trailing edge of the lower beam portion.
 28. The apparatus of claim25, wherein the beam includes an upper beam portion, a lower beamportion, and a central web portion connecting the upper beam portion andthe lower beam portion, and the central web portion has a minimum widthapproximately in a range of 50% to 100% of the greater of the upper beamportion's width and the lower beam portion's width when measured in aproximal to distal direction.
 29. The apparatus of claim 25, furthercomprising a control handle configured to actuate receiving, clampingand stapling of tissue, and a shaft coupling the control handle to thefirst jaw and the second jaw, wherein the first jaw and the second jaware collectively sized to pass through an esophagus.
 30. The apparatusof claim 25, wherein the first jaw and the second jaw are pivotablycoupled at a pivot point, one of the first jaw and the second jawincludes an overhanging flange at a proximal end that extends past asurface of the other of the first jaw and the second jaw when the firstjaw and the second jaw are in the first configuration and the secondconfiguration.
 31. The apparatus of claim 25, further comprising one ormore actuators including at least one of an actuator handle, a lever, atrigger, a knob or a cable.
 32. The apparatus of claim 25, wherein atleast a portion of the apparatus is powered.
 33. The apparatus of claim25, wherein at least a portion of the first jaw and the second jaw iscurved.
 34. An apparatus, comprising: a head portion having a first jawand a second jaw configured to move between a first configuration forreceiving tissue and a second configuration for sealing tissue; a beamhaving an upper portion and a lower portion connected by a central webportion, wherein the upper portion and the lower portion are configuredto clamp and align the first jaw and the second jaw at least partiallyfrom therewithin when in the second configuration as the central webportion moves distally along a channel defined in a tissue contactingsurface of each of the first jaw and the second jaw; a control handleconfigured to actuate receiving, clamping and sealing of tissue; and ashaft coupling the control handle to the head portion.
 35. The apparatusof claim 34, wherein the central web portion is configured as a cuttingblade, and the upper portion and the lower portion are configured toclamp and align the first jaw and the second jaw entirely fromtherewithin.
 36. The apparatus of claim 34, wherein the first jawdefines a cavity configured to receive a plurality of staples and aplurality of slots configured to pass said staples therethrough; thesecond jaw has a staple-forming surface; and at least a portion of thebeam positioned within the first jaw is configured to cause a staplepusher to move for firing a staple as the beam moves distally.
 37. Theapparatus of claim 36, wherein the central web portion has a leadingedge generally more distal than a trailing edge of the upper portion anda trailing edge of the lower portion and has a width approximately in arange of 50% to 100% of the greater of the upper portion's width and thelower portion's width when measured in a proximal to distal direction.38. The apparatus of claim 34, wherein the head portion is movablycoupled to the shaft.
 39. The apparatus of claim 34, wherein the headportion is sized for laparoscopic surgery.
 40. The apparatus of claim34, wherein the control handle includes at least one of an actuationhandle, a lever, a trigger, a knob and a cable.
 41. The apparatus ofclaim 34, wherein the apparatus is powered.
 42. The apparatus of claim41, wherein the apparatus is powered electrically, hydraulically orpneumatically.
 43. The apparatus of claim 34, wherein one of the firstjaw and the second jaw includes an overhanging flange at a proximal endthat extends past a surface of the other of the first jaw and the secondjaw when the first jaw and second jaw are in the first configuration andthe second configuration.
 44. The apparatus of claim 34, wherein atleast a portion of the first jaw and the second jaw is curved.
 45. Anapparatus for stapling tissue, comprising: a stapling head including afirst jaw and a second jaw, at least one of the first jaw and the secondjaw being movable to approximate with respect to the other of the firstjaw and the second jaw, the first jaw including a staple carryingportion and defining slots configured to pass staples therethrough andthe second jaw including a staple forming portion; and a beam having anupper portion and a lower portion connected by a central web portion,the upper portion and the lower portion being configured to engage thefirst jaw and the second jaw at least partially from therewithin,respectively, for clamping and alignment, the central web portion beingconfigured to travel along a channel defined in a tissue contactingsurface of each of the first jaw and the second jaw to clamp tissuetherebetween for stapling, and a portion of the beam within the firstjaw being configured to push a staple pusher for firing a staple as thebeam travels distally.
 46. The apparatus of claim 45, furthercomprising: a control handle configured to actuate driving of staplesthrough the slots and to approximate the first jaw and the second jaw;and a shaft coupling the control handle to the stapling head.
 47. Theapparatus of claim 45, wherein the central web portion is configured asa cutting blade and is configured to engage the first jaw and the secondjaw entirely from therewithin.
 48. The apparatus of claim 45, whereinthe beam is an I-beam, and the central web portion is configured as acutting blade, a leading edge of the cutting blade being generally moredistal than a trailing edge of the upper portion and a trailing edge ofthe lower portion, and the central web portion having a widthapproximately in a range of 50% to 100% of the greater of the upperportion's width and the lower portion's width when measured in aproximal to distal direction.
 49. The apparatus of claim 45, wherein oneof the first jaw and the second jaw includes an overhanging flange at aproximal end that extends past a surface of the other of the first jawand the second jaw when the first jaw and second jaw are in the firstconfiguration and the second configuration.
 50. The apparatus of claim45, further comprises a pushing bar coupled to the beam and configuredto push the beam distally, the pushing bar being substantially longerthan the beam when measured in a proximal to distal direction.